


Infidelity (When the Brothers Cheat on MC)

by Jackalopes



Category: Shall We Date?: Obey Me!
Genre: Angst, Cheating, Gen, Gender-Neutral Pronouns, Hurt/Comfort, Infidelity, Not Beta Read, Other
Language: English
Status: In-Progress
Published: 2020-09-09
Updated: 2020-09-09
Packaged: 2021-03-06 23:26:59
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 2,599
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26377261
Author URL: https://archiveofourown.org/users/Jackalopes/pseuds/Jackalopes
Summary: Taken from my HCs of if the brothers cheated on MC. I've turned them into angsty one-shots. MC is gender neutral. I only have Lucifer's written so far and Mammon is next.Not beta read
Relationships: Lucifer (Shall We Date?: Obey Me!) & Reader, Lucifer (Shall We Date?: Obey Me!)/Original Character(s), Lucifer (Shall We Date?: Obey Me!)/Reader, Lucifer/Main Character (Shall We Date?: Obey Me!), Main Character/Mammon (Shall We Date?: Obey Me!), Mammon (Shall We Date?: Obey Me!)/Reader
Comments: 5
Kudos: 108





	1. Lucifer

You found out when what was supposed to be a harmless prank revealed his secret. You had snuck into Lucifer’s study to put googly eyes on his stapler, tape dispenser, and computer monitor when you noticed his jacket draped over the back of his chair. It had an unfamiliar scent on it, not like his usual cologne. Was that perfume?

You also noticed a strand of hair on the collar of his shirt that was long and red. You knew no one who had long, red hair but still wanted to give him the benefit of the doubt.

You put the googly eyes away for another time as your lighthearted mood shifted to an anxiety filled one and you turned to leave. In your haste, you brushed against a stack of papers that fluttered to the ground. You turned around and quickly gathered them up, setting them on top of his desk. A letter with a lipstick kiss on it caught your eye.

You couldn't help yourself and picked up the letter, quickly scanning over its contents. Suddenly everything made sense. The days where Lucifer told you he got called to Diavolo’s all of a sudden and the days where he told you he had to work late were the same days this letter referenced. The sender had stated how much they enjoyed their time with Lucifer and to hurry up and dump that bothersome human already.

A wave of nausea washed over you as you lost your grip on the letter. It fluttered to the floor. The shock and utter disbelief was too much for you and you ran out of his study and to your room, locking yourself inside. You instantly fell to the floor, your legs turned to jelly as the feelings of betrayal and grief blossomed in your chest.

You needed to get out of here. Out of a house under Lucifer’s control. You forced yourself to stand as your knees shook, threw your suitcases on the bed, and haphazardly began shoving your belongings in them while dialing Diavolo's number on speakerphone. You couldn't go to Purgatory Hall or Lucifer would just demand you return to the House of Lamentation so Diavolo was your safest bet, if he was kind enough to let you stay with him, that is.

“MC? Is everything alright?” Diavolo had picked up on the first ring. He couldn't make out much of what you were saying between your choked sobs. “MC, I'm coming over. Stay there.” Diavolo was at your door within minutes and knocked softly. “MC, it's me, please let me in.”

You opened the door, eyes puffy and red while your body trembled from the sobbing. “Oh, MC…” Diavolo frowned as he pulled you into his arms. “P-please...get me out of here,” your voice was barely a whisper, as you looked up at the demon lord. Diavolo looked behind you and saw the suitcases. Normally, he'd asked you to explain but the desperation in your voice tugged at his heart strings so he took you back to his castle and had Barbatos prepare a guest suite for you.

Diavolo sat next to you on the bed as you told him what happened. Anger began to brew in the pit of his stomach. He would have never expected Lucifer to be capable of such a thing, let alone use him in the lies he told you. His fist clenched for a moment. He always had a soft spot for you and seeing you like this broke his heart.

“I am so sorry, MC. You can stay here for as long as you'd like. If you want to go back to the human world, say the word and I'll send you back.”

When you told him you wanted to finish out your year in RAD, he respected your decision and admired you for it. He altered your schedule so that you wouldn't run into Lucifer.

When Lucifer returned to his study later that day, he saw the letter on the floor, a feeling of dread knotted in his stomach. He tore the letter up in anger and crumbled its remains into a ball before he tossed it in the trash. He knew it had to be you that found it because if it has been one of his brothers, they'd have already let him know what an absolute scumbag he was.

The eldest brother blinked back the tears that were starting to form at the corner of his eyes and made his way to your room. He saw the door open and knocked softly before entering. “MC-” Lucifer faltered at seeing your room completely barren and you nowhere in sight. You were gone. He sat down on your bed and buried his face in his hands as he cried for the relationship he broke beyond repair.

He thought about calling you on your DDD, just to make sure you were safe but couldn't bring himself to press the call button. He saw an unread text from Diavolo and opened it. “MC will be staying at my castle for the remainder of their year. I have made some changes to their schedule. Do not contact them. I expect you to meet tomorrow morning before classes to discuss these changes.” Lucifer sighed, whatever punishment Diavolo had in store for him wouldn't be enough to right the wrongs he committed.

Meanwhile, at the castle, Diavolo did his best to make you feel at home. The two of you had grown close when you started dating Lucifer as you normally tagged along when he'd visit the castle. He had Barbatos bring you your favorite tea and pastry and let you have the option of taking off from classes tomorrow. You had opted to go. You weren't going to let Lucifer’s infidelity keep you from seeing your friends.

Lucifer told the brothers himself on the night that you left. They were angry. You had become like a sister to them. Diavolo had taken the time to message them privately and let them know they could come see you anytime as long as you were in the mood for company.

The next day was awkward. The brothers didn't know what to say to you and your friends at Purgatory Hall were not made aware of the situation yet. You let the brothers know you were going to be okay and insisted on carrying on like usual with them to distract you from your heartbreak. It didn't take long until the rest of your friends figured it out. Simeon had to physically restrain Luke from kicking Lucifer in the shin.

Diavolo did his best to make sure you didn't run into Lucifer for a while. You didn't want to talk to him or acknowledge his presence. You didn't need closure.

You refused to talk to Lucifer. You would not accept an apology from him either. He broke your trust after swearing on his life he'd never hurt you.

Over time your heart began to heal and you enjoyed your life at RAD once more. Your bonds with everyone deepened through the healing process and you were honestly not looking forward to graduation. Despite your heartbreak, you made friends for life and promised to keep in touch.

On graduation day, you held your head high, feeling a sense of accomplishment. You said your farewells and went home with a happy heart.

Lucifer was never quite the same. He couldn't forgive himself and his relationship with Diavolo and his brothers was strained. He tried to forget you and the joy that you brought into his life by burying himself in work. Anytime someone would mention your name in passing, he'd leave the room. When you came to visit his brothers and Diavolo, he made himself scarce. He was a fool but he was at least glad to see you were doing okay.


	2. Mammon

**Summary for the Chapter:**

> Mammon

Flash!

This was not what he had intended. 

Flash!

This was not what he had intended at all.

Mammon felt his blood run cold in the fading glow of the camera. A bubbly giggle came from the succubus as she finished snapping a selfie with the demon post-sex.

“Sorry! I just wanted a memento of our time together! I'll pay you double.”

Mammon didn't react as she threw the wad of cash at him. He just watched it smack him in the face and land on the floor. This was what he wanted, right? His numb fingers picked the bills off the ground. Human world currency? Another reminder of who he just betrayed. Why couldn't she just pay him in grim?

He froze at the feeling of lips on his cheek. 

“Come back again! You were amazing!” The succubus whispered in his ear.

“This is the last time. I don't care how in debt I am!” Mammon snapped, pulling his clothes on.

“Oh, you know you enjoyed it! You're the one who came to me after all. I just took you up on your offer.”

“This was a mistake! I don't ever want to see you again!” Mammon stormed out the door, slamming it shut behind him.

…

“Asmo, you are a lifesaver!” You exclaimed as the demon put the finishing touches on your look for date night.

“Always happy to help, my dear! My idiot brother will just eat you up on your date tonight!” 

“We've been seeing each other for months now yet I still have butterflies in my stomach,” you confessed as you paced around in your room.

“Oooh that's so cute! Come over here, Y/N! Let's browse Devilgram until Mammon gets here!” 

Asmo had made himself comfortable on your bed and patted the space beside him. You happily trotted over and watched as he scrolled through his feed.

“Oh that place is just to die for! It's got to be one of the most lavish clubs I have ever been to! We should go there sometime! Have you been to this restaurant yet, Y/N? They serve human world inspired food there! Their cupcakes are divine!” Asmodeus was babbling cheerfully to you as he flicked through his Devilgram feed before you both saw something that made your heart stop. Asmo’s ramblings tapered off into a stunned silence as the DDD fell from his hand and bounced softly on your bed. You scrambled to pick it back up, your heart hammering in your chest.

“Maybe it's from before you got together!” Asmodeus suggested as he took the DDD and zoomed in on the picture.

Mammon was wearing the chain necklace you bought him just the other week.

Asmodeus glowered angrily at the picture. How could his older brother do something like this to you?!

“Y/N?” The fifth-born softly spoke your name, concern in his eyes.

You remained still, eyes glossy with tears threatening to spill out. Your facade began to crack as your body started trembling. The shock subsided and grief took its place.

Before you could do anything else, Asmo pulled you into a tight embrace. “Y/N, honey, I'm so sorry,” he murmured comfortingly against your hair as he stroked your back.

As if on cue, Mammon walked through the door and instantly froze at the sight before him. Asmodeus looked up, pure rage in his eyes. You had never seen him so angry before. His demon form came out and he stood from the bed, shielding you from Mammon.

“Get. Out.” The younger brother warned.

“I'm sorry, Y/N! I can explain!” Mammon brushed passed Asmodeus to try and get to you.

A perfectly manicured hand on his shoulder suddenly yanked him back, hard. Mammon let out a yelp as he landed on the floor.

“I think that photo explains itself, Mammon. Now get out!” Asmo yelled in a tone you never heard him use.

“What in the demon lord’s name is going on here?” Lucifer growled as he rounded the corner into your room.

You were frozen on the bed, tears streaming down your face as Asmodeus glowered down at Mammon who was still on the floor.

“What did you do?” Lucifer asked, eyes narrowed at Mammon.

“I needed the money! It was a one time thing!” Mammon hastily explained and rose to his feet. “Y/N! I'm so sorry! I wasn't thinking!”

“Leave,” Lucifer ordered Mammon before coming over and kneeling by your bed. He gently took your hands in his. “What can I do?”

“I…” you bit your lip but continued, “don’t know.” You started to sob again and Lucifer pulled you into an embrace, letting you cry on his shoulder.

Despite how hard he was on Mammon, Lucifer thought highly of him. He respected Mammon’s kindness and his loyalty. To say the eldest was disappointed would be an understatement. He never expected something like this out of Mammon and he felt like he failed you. Lucifer trusted Mammon to look after you and protect you. Guilt began to gnaw at him as he held you. He swore then and there he would be the one to look after you instead of Mammon going forward, no matter how busy he was.

Lucifer and Asmodeus spent hours comforting you. You cried yourself to sleep in their arms. Lucifer frowned as he stroked your hair.

“Get some rest, Asmodeus. I will look after them tonight.”

Asmo frowned and wiped a few stray tears from your cheek before he stood up and bid Lucifer goodnight.

Word travels fast in the House of Lamentation. If the fighting didn't draw the attention of the remaining brothers, the Devilgram post making rounds certainly did. They all wanted to go to you as soon as they heard but Lucifer told them to give you space so as to not overwhelm you.

It took a lot of self control and restraint for some of the brothers not to just let loose on Mammon. Lucifer thought of punishing him but decided against it. It appeared that Mammon was doing a good job of that himself. He was distraught and broken without you and he had no one to turn to as everyone was upset with him.

As ideal as it would have been for things to go back to normal in the House of Lamentation, they didn't. There was a rift between Mammon and his brothers and between Mammon and you. You avoided him as much as possible and he gave you space. The first few weeks were the hardest as you were used to having him by your side for most of the day. In his place, his brothers stepped in to ensure your safety and well-being.

Your relationships with the other brothers strengthened over the remainder of the year. When you left the exchange program it was a bittersweet affair. You were glad you wouldn't have to see Mammon again but you would miss his brothers and the other friends you made during the exchange program. You promised to keep in touch and visit each other. You moved on with your life.

Mammon was never quite the same. At first he fell into his vices and his gambling addiction became worse. It was only when he hit rock-bottom that he started to change his toxic behaviors. It was too late to regain your trust but he could ensure that he wouldn't hurt anyone else like that in the future. He would always miss you and the relationship you had. You were special to him. Gradually, his relationship with his brothers improved with time.

Maybe someday in the future you could be friends again but for that, it would take a lot of time.

**Notes for the Chapter:**

> Next chapter will be Levi


End file.
